139774721 has 2 divisors, whose sum is σ = 139774722. Its totient is φ = 139774720.

The previous prime is 139774709. The next prime is 139774763. The reversal of 139774721 is 127477931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 132135025 + 7639696 = 11495^2 + 2764^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-139774721 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (139774021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69887360 + 69887361.

It is an arithmetic number, because the mean of its divisors is an integer number (69887361).

Almost surely, 2^139774721 is an apocalyptic number.

It is an amenable number.

139774721 is a deficient number, since it is larger than the sum of its proper divisors (1).

139774721 is an equidigital number, since it uses as much as digits as its factorization.

139774721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 74088, while the sum is 41.

The square root of 139774721 is about 11822.6359581948. The cubic root of 139774721 is about 518.9707464055.

The spelling of 139774721 in words is "one hundred thirty-nine million, seven hundred seventy-four thousand, seven hundred twenty-one".